Revolving doors provide a means for entering or leaving a building or room in an orderly fashion and in such a manner as to converse heating or cooling energy within the building or room. Further, revolving doors are capable of permitting persons to pass therethrough without using their hands. Specifically, revolving doors include a cylindrical housing disposed or incorporated into the wall of the building or room. Within the housing is a rotatable shaft mounting a plurality of panels which extend outwardly from the shaft to closely adjoin the housing. Between any pair of adjacent panels a cylindrical sector-shaped compartment is defined which revolves upon rotation of the shaft between an entrance and an exit provided in the housing to move a person through the revolving door.
To pass through the revolving door, a person enters the door at either the entrance or exit and steps into a a compartment. Pushing against a panel, the person causes the shaft to rotate and the panels to revolve so that the compartment travels around the housing to ultimately pass the person through the door. As can be appreciated, for large revolving doors, a relatively strong push is required to overcome the inertia of the door to revolve the panels and pass the individual through the door. Further, the panels typically have seals which bear against the housing to prevent air from escaping through the door. When these seals are new a large force is required to overcome the frictional engagement with the housing which, when combined with the force necessary to overcome inertia, makes it difficult for most persons, and especially the elderly, handicapped or those with their hands full of goods to pass through the door.
To overcome this problem, it has been known to provide motors to revolve the panels and the compartments between the entrance and exit. For example, in U.S. Pat. No. 4,341,165 issued to Calandritti et al on July 27, 1982, a motor is provided which is actuated by a switch located at one of the panels. To pass through the door, the person depresses the switch which activates the motor to revolve the panels. In Carroll et al U.S. Pat. No. 4,295,297, issued Oct. 20, 1981 a sensor either of the infrared or microwave type is positioned to sense the approach of a person and to activate a motor to revolve the panels. These systems, however, are expensive and complicated, detracting from the reliability of the door.